RecruitingPhase 2Drug trialOxaliplatin and Liposomal Irinotecan (Plus Trastuzumab for HER2-positive Disease) in Advanced Esophageal and Gastric AdenocarcinomaThis is an open label, phase II, multi-site trial evaluating the efficacy and safety of the combination of 5-FU, oxaliplatin, nal-IRI, and immunotherapy (plus trastuzumab for HER2-positive tumors) as first-line therapy for participants with advanced Esophageal and Gastric Adenocarcinoma (EGA). The investigators hypothesize that this drug combination will be better tolerated than current first-line chemotherapy combinations for this disease.